Category: Broadcast Radio

Testing DAB Decoders: SDRAngel versus Welle.io

Thank you to the team from DXing.org for submitting their video where they compare the DAB decoding performance of SDRAngel and Welle.io using an RTL-SDR Blog V3 dongle.

Digital Audio Broadcast (DAB) is a digital replacement for analog broadcast FM. It provides high quality digital audio at the expense of higher cost receivers, and possibly greater difficulty with reception in weak or challenging RF environments. DAB is mostly only used in Europe and Asia Pacific regions, and is not found in the USA. SDRAngel and Welle.io are both RTL-SDR compatible programs with DAB decoding capabilities. Both can run on Android, PC, MacOS and Linux devices.

In their tests they find that the Welle.io DAB decoder works perfectly without issues, however the SDRAngel DAB decoder struggles and has difficulty with decoding. Given that Welle.io is a dedicated DAB decoder, and SDRAngel is a multipurpose tool this could be expected. But we are unsure what is wrong with the DAB implementation in SDRAngel.

The team note that the test was carried out in Sofia, Bulgaria, Europe, using a Serbian DAB+ signal from Yastrebac, with a distance of 175km.

Test android apps with DAB+ signal Welle.io vs. SDRangel, receiver rtl-sdr v.3

Guglielmo FM and DAB Receiver Software Updated to Version 0.5

Thank you to Marco, the programmer of Guglielmo for letting us know that his software has recently been updated to Version 0.5.

Guglielmo is a Linux, Windows (and in this recent update x86 MacOS) based RTL-SDR FM and DAB tuner software that supports SDRs including the RTL-SDR, Airspy, SDRplay, HackRF and LimeSDR. It is designed to be an easy to use program designed for media users, rather than hobbyist technical users.

Regarding the release of Version 0.5, Marco writes:

This release sports full mac (x86 only, sorry) and windows installers, DAB and FM scans and a preset editor.

Guglielmo: Screenshot of the DAB Interface

SDRangel Now Available on Android: Mobile ADS-B, AIS, APT, Digital Voice, POCSAG, APRS, RS41 Radiosonde Decoders

SDRangel is a free open source software defined radio program that is compatible with many SDRs, including RTL-SDRs. SDRAngel is set apart from other programs because of it's huge swath of built in demodulators and decoders.

Thank you to reader Jon for writing in and noting that SDRangel has recently been released for Android as a free Google Play download. This is an amazing development that could open up many doors into portable decoding setups as the Android version supports almost every decoder implemented on the desktop version. Jon writes:

It includes most of the functionality of the desktop version of SDRangel, including:

  • AM, FM, SSB, Broadcast FM and DAB, AIS, ADS-B, Digital Voice (DMR, dPMR, D-Star, FreeDV), Video (DVB-S, DVB-S2, NTSC, PAL), VOR, LoRa, M17, Packet (AX.25), Pager (POCSAG), Radiosonde (RS41), Time signal (MSF, DCF77, TDF and WWVB) modems.
  • RTL SDR, Airspy, Airspy HF, LimeSDR, HackRF and SDRplay support via USB OTG as well as networked SDRs
  • 2D and 3D signal analysis in both time and frequency domain with statistical measurements of SNR, THD, THD+N, SINAD, SFDR and channel power
  • Satellite tracker, star tracker, maps and rotator controller

It should work on Android 6 and up. It’s a straight port of the desktop application, so although it will run on a phone, probably best used on a large tablet with a stylus or mouse.

SDRangel on Android
SDRangel on Android
SDRangel

The SDRSharp ListenInfo Plugin

SDR# is a popular software defined radio program that is compatible with RTL-SDR, Airspy and several other SDR devices. One feature is the ability for third parties to develop plugins for the software.

One recently released plugin that is gaining popularity is the "ListenInfo" plugin. The ListenInfo plugin uses a publicly available database of shortwave stations to display frequency station info for the LW, MW, SW bands within the SDR# spectrum display.

If you've ever been browsing the shortwave bands and wondered where a station is broadcasting from, and what it's transit power, beam direction and transmit schedule are like, then this will be a very useful plugin for you.

SDR# ListenInfo Plugin
SDR# ListenInfo Plugin

Guglielmo FM and DAB Receiver Software Updated to V0.4

Thank you to Marco Greco for writing in and noting that V0.4 of his Guglielmo software has recently been released.

Guglielmo is a Linux (and now Windows) based RTL-SDR FM and DAB tuner software that supports SDRs including the RTL-SDR, Airspy, SDRplay, HackRF and LimeSDR. It is designed to be an easy to use program designed for media users, rather than hobbyist technical users.

The latest additions in V0.4 include support for MPRIS controllers, support for the SDRplay V3 API and support for Windows building (although at this time there appears to be no binary file available).

The AppImage can be found here https://github.com/marcogrecopriolo/guglielmo/releases

Guglielmo: Screenshot of the DAB Interface

Using an SDR# Plugin to Tune into a Broadcast FM SCA Subcarrier (Radio Reading Service for the Blind)

Thank you to Double A again for submitting a new video where he shows how to use a new SDR# plugin called "SCATuner" to listen to an SCA audio subcarrier embedded within a broadcast FM signal.

SCA short for Subsidiary communications authority, is a separate audio channel hidden within a broadcast FM signal. SCA is typically used for niche radio programs, elevator music, music for doctors offices, and niche services such as reading for the visually impaired. In the past you needed a special hardware SCA radio to receive these channels, however receiving these channels with an SDR is relatively simple. Not all broadcast FM stations will have an SCA service, but the video shown below explains how to find one.

In previous posts Double A and others have shown how to receive these SCA Subcarriers using two instances of SDR#. However, this new plugin makes the task much simpler one click job.

Double A's video goes over how to install and use the plugin, explains SCA and demonstrates it in action decoding a radio reading service for the blind.

SDR# Plugin for Tuning an FM SCA Subcarrier (Radio Reading Service for the Blind) (with RTL-SDR USB)

Using an RTL-SDR to Decode Broadcast FM RDS Data on Android

Over on YouTube Double A Labs has posted a new video demonstrating how to use an RTL-SDR and Android device to receive broadcast FM stations, and to decode any associated RDS data. 

In the video Double A uses the SDR Touch Android app and the Advanced RDS function to show the RDS information. He goes on to explain the various pieces of information RDS data provides including clock time, active RDS groups and alternative frequencies.

Tune broadcast FM radio and decode Radio Data System (RDS) information using your Android phone and an RTL-SDR USB (see parts list below). RDS can include station identification, song name, the current time for a receiver to sync its clock, alternative frequencies the same program is on, and more!

Tuning FM Radio & Decoding RDS Data on ANDROID using RTL-SDR USB

DAB+ Decoder Welle.io Version 2.4 Released and YouTube Demonstration Video

Version 2.4 of the RTL-SDR compatible DAB/DAB+ decoder called welle.io has recently been released for download on GitHub. The main changes include various bug fixes, the addition of Windows 11 support, and the return of the Android APK (but only with rtl_tcp support).

The author has also released a new YouTube video tour, demonstrating the software in action, and explaining all the features.

Showing welle.io a SDR to listen DAB/DAB+.